Alternating-current rectifier.



n. P. STEINMETZ. ALTERNATING CURRENT RECTIFIER.

APPLICATION FILED AUG-24, I914 A 1,275,782. Patented A1 1grl3, 1918.

Witnesses: I Inventor":

Charles PSte inmetz;

by wwe CHARLES E. STEHTME'DZ, OF SUHENECTADY,

nicn.

NEW YOEIK, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

summarise-consent mam-ma.

ll ,2 T5, Td

specification of Letters Patent.

Patented Aing. as, this.

application filed August 24, ieia. $er'ia1lil'o.8'58,190.

To all whom it may concern:

Be it known that l, CHARLES P. firmn- :un'rz, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and usefui improvements in Alternating-fhirient Rectifiers, ofwhich the following is a specification.

My present invention relates to thereof/L fication of alternating currents, and more especially to the rectification of alternating currents of high potential. The object of my inventimi to provide method of and urea-us for rectifying alternating currents fOf higher potential than can conveniently be rectified by commercial forms of 'rectifiers in use at the present time, such, for example, as the mercury arc rectifier.

The phenomenon known as corona which is present in high PM GIlt-HQl distribution systems has been extensively investigated since systems of this nature have come into extensive use, and as a result of these investigations many of its varying characteristics have been discovered. Among other things, it has been discovered that if a metallic point has a high positive potential impressed thereon, the corona will extend out into the surrounding air for a considerable distance, while if an equal negative potential is ap= plied to the point there will be little or no corona formed. I propose to take advantage of this characteristic of the corona to accomplish the rectification of high potential alternating current.

In carrying my invention into effect, I produce, by means of the alternating current which is to be rectified, a corona dislit charge from a set of electrodes which are so positioned with respect to an electrode or electrodes connected to the direct current circuit that when any one of the first set of electrodes is positive the corona discharge.

therefrom will reach and be collected by the electrode connected to the direct current circuit. 0n the other hand, when any one of the first set of electrodes is negative, the

corona discharge therefrom will not extend out far enough to reach theelectrode connected to the direct current circuit. 1

In the accompanying drawing Figure 1 indicates diagrammatically a simple way of carrying my invention into efl'ect andFig. 2 shows a modification of-the arrangement shown in Fig. 1. The high potential cur- .erly speaking,

line conductors 7 is also connected to the ne-utrai point thus provided, While the other conductor 8 is connected to a third electrode 9 placed at a suitable distance from the electrodes 4 and 5. This electrmle may have any form-desired, and may also be pointed. The electrodes are preferably inade of some refractory metal, but the operation of the device is entirely independent of the material used for the electrodes or any dis similarity in their form.

TVhile in Fig. 1 I have indicated only a single set of electrodes, it will be apparent that a plurality of electrodes connected in parallel may equally well be employed, and also that a negativ. electrode 9 may be employed for each one of 'the positive electrodes as shown in Fig. 2 in case it is de sirab le. Current consuming devices 10 may be connected across mains 7- and 8.

The d'ista-noebetween the electrodes 4 and 5 the electrode 9 must be properly adjusted for the potential derived from the transformer. When it is thus adjusted, and the electrode 4:, for example, is positive, the corona therefrom will extend out far enough to reach the electrode-9, and there will be a transfer of energy between the electrodes,

without the formation of any dynamic arc i current consuming devices 10.

It Will, of course, be understood that the current obtained in this way is not, propa continuous current, but consists of a serles ofcurrent impulses. By the use of suitable arrangements of reactance and capacity to smooth out the irregularities in the Wave form, however, a continuous current may be obtained 111 case it is detit) sired. It will also be apparent that by varying the arrangement of the electrodes the same principle may be applied to the. rectification of a polyphase current.

What I claim as newand desire to secure by Letters Patent of the United States, is

1. Themethod of'rectifying an alternating current which consists in supplying the current to be rectified to suitable electrodes to produce successive corona discharges therefrom, positioning a collector element within striking distance of a positive corona discharge and beyond striking distance of a negative corona discharge, and collecting thereby the positive corona discharges to produce a unidirectional current.

2. The method which consists in applying an alternating current potential to suitable electrodes to produce successive corona discharges therefrom and collecting the discharges from said electrodes only when the electrodes are positive.

3. The combination in a system for the rectification of alternating currents, of a plurality of stationary electrodes, means for impressing an alternating potential upon said electrodes to produce successive corona discharges therefrom, and one or more stationary electrodes so positioned with respect to the first-named electrodes as to receive only the positive corona discharges.

4. The combination in a system for the rectification of alternating currents, of a.

high voltage transformer, a source ofalternating current connected thereto, electrodes connected to the terminals of the secondary of said transformer, one or more stationary electrodesso positioned with respect to thefirst-named electrodes as to receive the positive corona discharges therefrom, but not the negative, and a pair of conductors one of which is connected to a neutral point in the secondary of the transformer, and the otherof which is connected to the last-namcd electrode or electrodes.

5. The combination in a system for the rectification of alternating currents, of an electrode, means for impressing an alternating potential upon said electrode to produce successive corona discharges therefrom, and a stationary second electrode so placed with respect to the first that it will receive only the positive corona discharges.

6. The combination in a system for rectifying alternating currents of an electrode, means for producing successive corona discharges therefrom, and a stationary second electrode so placed with respect to the first that it will receive corona discharges of one polarity only.

7. The combination in a system for the rectification of alternating current, of means for producing successive corona discharges by the current which is to be rectified, and a collector element located within striking distance of the positive corona discharges and beyond striking distance of the negative corona discharges for collecting the positive corona discharges to produce a unidirectional current.

In witness whereof I have hereunto set my hand this 21st day of August, 1914.

CHARLES P. STEINMETZ. Witnesses:

BENJAMIN B. HULL, HFLEN Orronn. 

